Accession Number : AD0486737

Title :   ABLATIVE POLYMERS FOR HYPERSONIC ATMOSPHERIC FLIGHT.

Descriptive Note : Technical rept. Jul 65-Feb 66,

Corporate Author : AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OH

Personal Author(s) : Schmidt, Donald L.

Report Date : MAY 1966

Pagination or Media Count : 110

Abstract : Environmental conditions associated with hypervelocity flight in planetary atmospheres are reported in detail. These include such parameters as gas temperature, enthalpy, mode of energy transport, total heat load, peak heating rate, shape of heat pulse, duration of heating, external and internal pressure forces, gasdynamic shear, solid and liquid particle impact, mechanical and acoustical vibration, inertial and dynamic forces, and the chemical reactivity. The independent effect of these environmental factors is given for various polymeric materials. Ablative heat shielding is the most widely used form of thermal protection for hypervelocity atmospheric vehicles. Plastics, elastomers, ceramics, and metals have all been used to varying degrees, but of these compositions, polymers have clearly found the greatest utility. They include the depolymerizing types like polytetrafluoroethylene, charring resins such as phenol formaldehyde, charring elastomers like aromatic silicones, melting fibrous reinforcements such as nylon, and others.

Descriptors :   *ABLATION), *PLASTICS), (*POLYMERS, (*HYPERSONIC FLIGHT, HEAT SHIELDS), (*COMPOSITE MATERIALS, ATMOSPHERE ENTRY, TEMPERATURE, ENTROPY, DYNAMICS, COOLING, HEAT SINKS, MAGNETOHYDRODYNAMICS, POLYETHYLENE PLASTICS, HALOCARBON PLASTICS, PHENOLIC PLASTICS, FORMALDEHYDE, ELASTOMERS, NYLON, SIMULATION, ATMOSPHERE ENTRY, FURNACES, AIR, ARC HEATERS, SHOCK WAVES, FLIGHT TESTING, NOSE CONES, SPACE CAPSULES, SILICONES.

Subject Categories : Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE